Family gathered to mark what would have been Ms McConville's 80th birthday

Children of IRA murder victim Jean McConville have vowed to continue fighting for justice as they gathered to mark what would have been her 80th birthday.

Relatives planted a tree and released doves into the air during a poignant ceremony of music and prayer at a victims' support centre in north Belfast.

The event was held as police announced that a 56-year-old man had been re-arrested in connection with the notorious 1972 abduction and killing of the Belfast mother-of-ten.

The suspect was originally detained by officers last month but the interview process was halted due to a medical issue arising.

Seven people have been arrested and questioned in the last two months in connection with the murder - the most high profile being Sinn Fein president Gerry Adams.

Mr Adams, 65, was released on Sunday without charge after four days in police custody. A police file is to be passed to prosecutors to determine whether any charges will be pursued. Mr Adams vehemently denies any involvement in the crime.

"We know it's going to be a long road to try and get justice for our mother, we know all these events when they take place we know we are going to go through a hard time," said Mr McConville.

"We have been backed into a corner by the IRA and we are going to come out fighting and we want justice for our mother."

Mr McConville reiterated the family's call for the case to be handled by the International Criminal Court in the Hague citing concerns about political interference with policing in Northern Ireland.

"We want our mother's case to be taken out of Northern Ireland," he said.

"We want it brought it to the Hague, we want an independent body to look at this, we don't want anyone here to be looking at it."

(Photo: Niall Carson/PA Wire)

He said he and the other children lived in hope that one day justice would be obtained.

"I don't know whether it will ever come but we are hoping it does come and the length of time I am on this earth I will be fighting every day to get my mother's case heard in the proper manner."

In March veteran republican Ivor Bell, 77, from Ramoan Gardens in west Belfast, was charged with aiding and abetting the murder and IRA membership.

Police are preparing files on four women also detained in connection with the murder for Northern Ireland's Public Prosecution Service (PPS).

Mrs McConville, a 37-year-old widow, was dragged, screaming, away from her children in the Divis flats in west Belfast by a gang of up to 12 men and women after being wrongly accused of informing to the security forces.

She was interrogated, shot in the back of the head and then secretly buried - becoming one of the "Disappeared" victims of the Troubles. Her body was not found until 2003 on a beach in Co Louth, 50 miles from her home.

Families of Disappeared victims whose remains have yet to be discovered joined members of the McConville family at today's event.

Mr McConville said he hoped they would all ultimately get the chance to give their loved ones a proper burial.

"I'd love to see all the bodies returned, I would like to see all the bodies returned to their loved ones so they can get a Christian burial," he said, calling on those involved in their murders to come forward with information.

The Independent Commission for the Location of Victims Remains (ICLVR), the body established by the British and Irish Governments to recover the remains of the Disappeared, has stressed again that any information that is given to the Commission is treated in the strictest confidence and will never be shared with other official agencies.

Commissioners Sir Ken Bloomfield and Frank Murray said: "In light of the media attention of recent days and commentary referring to the Disappeared, we feel it is important to make it absolutely clear that anyone who comes to the ICLVR with information relating to the location of the remains of those victims yet to be recovered can do so with complete confidence.

"The work of the ICLVR is entirely information driven and is focused solely on recovering the remains of the victims for the sake of their families. All information that is given to the ICLVR to help us recover those victims can only be used for that purpose."

The suspect arrested in connection with the McConville case presented himself at Antrim police station this morning.

A Police Service of Northern Ireland (PSNI) spokesman said: "Detectives from Serious Crime Branch investigating the abduction and murder of Jean McConville in 1972 have arrested a 56-year-old man in Co Antrim. He is being questioned in the Serious Crime Suite at Antrim police station."